Not yet built. When Blueprint is ready to publish, mirror the Jekyll layout used by the sibling specifications rather than inventing a second one: _config.yml, _layouts/, _includes/, assets/css/style.css, and the index.md, spec.md, contributing.md pages.
CNAME is set to blueprint-spec.dev. That host is also the $id prefix for every file under schema/v1/, so changing the domain is a schema change and is at minimum a MINOR version bump.